IT'S OFFICIAL: Here's the new small iPhone SE

Steve Kovach/Tech Insider Apple unveiled its latest iPhone, the iPhone SE, at an event on its Cupertino, California, campus on Monday.

It's going to cost $399 without a contract, or free with a two-year contract — significantly less expensive than other new iPhones were when they first launched.

You can preorder it on March 24, and it will go on sale in stores on March 31.

The SE has a similar body to the iPhone 5S, but with updated components.

"It's got advancements that will make it the most powerful 4-inch phone ever," Greg Joswiak, head of iPhone marketing, said.

According to Apple, the SE will have the same processor as the 6S. The A9 chip in the SE will allow it to turn on when a user says "Hey Siri" and will enable Apple Pay, which is a way to use an iPhone to pay at certain credit-card terminals.

The iPhone SE will also have a 12-megapixel camera, which should be as good as the camera currently in the iPhone 6S. It will also be able to take Live Photos, an Apple photography feature that adds subtle movement to a still picture.

The SE comes in rose gold, a pinkish finish previously available only on the iPhone 6 and 6S.

One banner feature the SE will lack is 3D Touch, a new type of multi-touch technology that lets the iPhone sense how hard the user presses down.

Apple is hoping that the iPhone SE can tap into an underappreciated market — people who like small phones — and can help turn around sluggish iPhone sales trends by accelerating existing users' upgrade cycles.

Data show that one-third of iPhone users are still using a 4-inch iPhone, and analysts have predicted that Apple could sell as many as 15 million iPhone SE units in its first year.